-ktə(r) noun
( -s )
1. : one that ejects: as
a. : the mechanism of a firearm that ejects the empty cartridge
b. : a device that ejects finished work (as a cast slug) from the mold of a typecasting mechanism or the die of a die-casting mechanism or hydraulic press
the casting is removed by pressure from ejector pins fastened to the ejector plate behind the movable die — David Basch
2. : a jet pump for withdrawing a gas, fluid, or powdery substance (as air, water, or sand) from a space